Decorative and acoustic composition



. Aug. 28 1934.

c. .1. CERVENY El AL 1,971,900 DECORATIVE AND ACOUSTIC COMPOSITION Filed May 9, 1935 -HARD SURFACE OF SLOW-SETTING BINDER 3) EXPANDED l ERM/CUL/TE rTH/A/ FILM 0F WAX GUM 0/? RES/Al EXPANDEp VERM/CUL/TE ZHARD SURFACE OF SLOW-SETTINS BINDER IN i s/v T0 R5 CHARL ES cm VENV HUGH EVANS.

BY Jim/4M4 A TTO/PNEVS.

' 50 sired thickness Patented Aug. 28,

DECORATIVE AND ACOUS'I'I COMPOSITION I Charles J. Cerveny, Elmhurst, and Hugh Evans,

Floral Park, N Y.

Application May 9, 1933, Serial No. 670,208

9 Claims.

Our invention relates to surface plaster coatings for walls, ceilings, cornices, columns, pulpit sounding boards, lighting fixtures, or any of the other decorative fixtures that are commonly employed in architectural design, and has for its principal object the provision of a surface coat ing which is to be applied by conventional manner and in which valuable acoustic properties are combined with decorative 1o appearance. Our invention is concerned primarily with the provision of a surface coating of the type described containing an expanded vermiculite such as zonolite, jeiferisite, etc. and a treatment of such coatings to increase their hardness and accentuate the decorative effect thereof.

Throughout the specification and claims, whenever a wall is referred to it is to be understood that any of the other surfaces enumerated above .is intended as well. go We are aware of the fact that zonolite has been used in conjunction with plaster'in the manufacture of plaster board (Patent No. 1,778,008), as asubstratum for acoustic plaster (Patent No.

1,839,887) and as an insulating material in safes of insulating bricks and similar-molded insulat ing material (Patent No. 1,693,015). We are also aware of the fact that zonolite has been used as an insulating material in combination with so- 3 dium silicate and copper oxide (Patent No. 1,776,-

749), in combination with bentonite and'other materials (Patent No. 1,830,253), and in combination with hydrated lime. and diatomaceous earth (Patent No. 1,812,306) and in a roofing composition in combination with asphalt andbumt clay (Patent No. 1,743,744). So far as we know, however, expanded vermiculite has never been used in combination with a plaster or a cement as a finish coat to be applied by a trowel in the 40 conventional manner to the walls of a room for the purpose of improving the acoustics of a room and improving the appearance of the walls.

It the acoustics of a room are poor we have found that we can improve them considerably 5 by applying to the walls a coating of a composition essentially composed-of expanded vermiculite and one of the customary cements, such as Portland cement or Keenes cement, preferably the latter. This coating can be of any dedepending on the amount by which it is desired to improve the acoustics of the room. The improvement in the acoustics increases directly with the thickness of the coating. Likewise, when a room requires decoration, we have found that our composition is much more a trowel in the,

(Patent No. 1,715,977) and in the manufacture suitable for this purpose than the usual paints or decorative papers or fabrics. When our composition is first applied to a wall it has a mottled gray appearance. By rubbing it down with sandpaper, steel wool or some similar abrasive, the color effects of the expanded vermiculite are brought into prominence. The surface so produced is entirely satisfactory for decorative and acoustic purposes but has the disadvantage that if a portionof it is washed to remove a spot or stain the washed portion has a difierent shade from the remainder of the surface. We have found that this disadvantage can be eliminated and at the same time the surface can be given a glossy appearance and increased hardness by treating the surface with a thin solution in an organic solvent of a wax, gum, resin, either natural or artificial, or Irish'moss. Among the gums, resins and waxes which are suitable for this p p se are gum tragacanth, gum copal, gum arabic, beeswax, Montan wax, carnauba wax, paraffin'wax, soluble urea aldehyde resins, soluble phenol aldehyde resins, rosin and other vegetable resins. The solvent employed is usually benzine, benzene or alcohol. The solution can be sprayed so on or applied with a brush, the former method being preferable. When the surface has dried after the application of the solution, it is polished with a soft cloth. Y

a As a base coat for our finish coat we can use 5 any of the common base coats or we can use a base coat containing expanded vermiculite in conjunction with a cheaper binder than that employed for the finish coat. The finish coat can contain any desired mineral pigment. Striking 9o effects can be produced by the selection of a mineral pigment of the proper color in conjunction withthe expanded vermiculite. We have also found that a very good decorative effect is produced by using fine chips obtained by breaking a5 up sea-shells instead of or in conjunction witl. the expanded vermiculite. These chips of seashells impart a silver tone to the surface.

While ordinary quick setting gypsum plasters, such as plaster of Paris, can be used as binders for expanded vermiculite, such material is unsuitable for the purpose of our invention because, by

reason of the quick setting properties of these materials, it is impossible to utilize them in a composition which is to be applied to a wall by a trowel. The reason for this is that any composition that is applied to a wall by a trowel must be subjected to considerable working before the proper finish is obtained. In the case of these quick setting materials, sufficient time is not perafter applying such materials. Such materials usually go dead after being on a wall for a short period of time and thereafter are incapable of 5 being worked. These materials have the additionaldisadvantage that they deteriorate very rapidly and are consequently impractical, Of course, it is possible to make these materials more suitable by the use of retarders of a chemical or physical nature. The use of these retarders is, however, not especially desirable because of the added expense and increased difilculties in working and because the durability of the coatings produced is not increased to any noticeable degree by the inclusion of a retarder.

There are several hard, ually slow setting gypsum plasters, however that we have found to be quite suitable for our compositions. These plasters have nothing in common with plaster of Paris, except the fact that they are all obtained from gypsum rock. Most typical of this class of materials is Keenes cement referred to above.

We have further found that very good decorative and acoustic coats can be obtained by mixing expanded vermiculite, preferably ground to about one-sixteenth mesh, with one of the substances commonly known as protective colloids and including glue, gelatine, vegetable mucilage and gums. The mixture is made by converting the protective colloid to the liquid state, if it is not already in that state, and mixing it thoroughly with. the expanded vermiculite in proportions such that a mixture is obtained having the consistency of dough. This mixture can'be applied to any substratum, such as glass, wood, metal, plaster or stone in comparatively thin layers, or, if desired, in thick layers. As soon as the coating is hardened and dried, it is treated in much the same manner in which the plaster compositions are treated, namely, rubbed with an abrasive until smooth and, if desired, coated with a thin lacquer-like solution of a natural or artificial gum, wax or resin. It is usually suflicient to use the protective colloid in an amount approximating fixe percent of the amount of expanded vermiculite employed. The surfaces produced from this composition are characterized by a golden lustre which can be accentuated by the addition to the composition of mineral pigments of any desired color.

When a cement such as Keenes cement or Portland cement is used as the binder for expanded vermiculite the mixture of cement and vermiculite can be cast into plates or blocks to form a very serviceable and extremely desirable artificial stone. These plates can be made of any desired thickness and are especially advantageous in thicknesses ranging from about one-half to one inch as a covering for walls and other exposed surfaces requiring decoration.

A wall surface according to our invention is illustrated in the accompanying drawing in which Fig. 1 is a face view and Figi2 is a sectional view. Suitable legends appear on the face of the as drawing whereby further description thereof is unnecessary. It is to be noted, however, that the expanded vermiculite on the surface has a fiat face fiush with the face of the binder. This is the result of the treatment with the abrading 7o agent. It is also to be noted that in Fig. 2 the thickness of the film of wax, gum or resin is exaggerated for the purpose of illustration.

Our invention is more specifically described in the following examples which are illustrative rather than limitative.

mitted the operator to properly finish the wall Example 1 A mixture of one part of slow setting gypsum plaster, such as, slow setting bonding plaster, and three parts of zonolite is worked up with sufficient water into a plastic mass which is applied to a wall with a trowel. After a coating of uniform thickness has been applied and floated it is allowed to dry. The coating is then rubbed with sandpaper or steel wool or some other similar abrasive and brushed clean of dust. The wall is then sprayed with a thin solution of gum arabic in benzine and allowed to dry again after which it is polished with a soft cloth.

Example 2 any desired thickness. Upon setting and hardening, the plates so produced have the appearance of stone. If a colored surface is desired for the plate, a saving in color can be efiected by filling the mold nearly to the desired depth with an uncolored mixture and filling the remainder of the mold with a mixture to which the desired color has been added. In this way, the colored layer can be made as thin as one-sixteenth of an inch. Similar results are obtained when Portland cement is used in place of Keane's cement and when Irish moss or beeswax is employed in place of gum arabic in the g solution.

Example 3 body of the coating. The surface is rubbed down with an abrasive until it is perfectly smooth. If desired, it is then sprayed with a thin solution of any of the natural or artificial gums, waxes or resins enumerated above.

When it is desired to add a mineral pigment to any of the above compositions, the pigment is added in a finely ground state in an amount ranging from six to ten percent of the total com,- position. Of course, the pigment is added during the manufacture of the mix so as to be uniformly J dispersed therein.

Having thus described our invention and illustrated the preferred embodiments of the same, what we now claim as new and useful and desire to secure by Letters Patent is: 1

i. A finish coat for a wall comprising expanded, vermiculite and a substance selected from the group consisting of slow setting gypsum plasters, cements and protective colloids, the expanded vermiculite being exposed on the surface of said finish 1% coat as brilliant particles.

2. A finish coat for a wall comprising a slow setting gypsum plaster and expanded vermiculite, the expanded vermiculite being exposed on the surface of the finish coat as brilliant particles.

3. A finish coat for a. wall comprising gum arabic and expanded vermiculite, the expanded vermiculite being exposed on the surface of the finish coat as brilliant particles.

a A finish coat for a wall comprising a binder 1 selected from the group consisting of slow setting gypsum plasters, cements and protective colloids and exposed brilliant particles of expanded vermiculite with a thin surface coating of a substance selected from the group consisting of gums, waxes and resins.

5. A finish coat for a wall comprising a slow setting gypsum plaster and exposed brilliant particles of expanded vermiculite having a thin surface coating of a substance selected from the group consisting of gums, waxes and resins.

6. A method of decorating walls which comprises applying thereto a layer of a composition comprising a binder selected from the group consistlng of slow setting gypsum plasters, cements and protective colloids and expanded vermiculite, allowing the layer to dry, rubbing the surface of the layer with an abrading agent and brushing the surface clean of dust whereby brilliant particles of vermiculite are exposed on the surface.

7. A method of decorating walls which comprises applying thereto a layer of a composition comprising expanded vermiculite and a substance selected from the group consisting of slow setting gypsum plasters, cements and protective colloids, allowing the layer to dry, rubbingthe surface of the layer with an abrading agent, brushing the surface clean of dust whereby brilliant particles of vermiculite are exposed on the surface and applying to the surface so formed a thin solution in an organic solvent of a substance selected from the group consisting of gums, resins and waxes.

8. A method of correcting the acoustics of a a room which comprises applying to exposed surfaces thereof a mixture containing gum arabic and zonolite, allowing the mixture to dry whereupon the zonolite projects from the matrix of gum and rubbing the surface with an abrading agent until the zonolite is flush with the matrix of gum whereby brilliant particles of vermiculite are exposed on the surface.

9. An artificial substance having a density and hardness approximating that of stone and comprising expanded vermiculite and cement, the expanded vermiculite being exposed on the sur-= face of said substance as brilliant particles.

CHARLES J. CERVENY. HUGH EVANS. 

